Making Amazon AWS API Queries

__init__.py

README

Very simple wrapper for signed and authenticated Amazon API queries.
Works with most Amazon AWS APIs and various other services.

The APIs themselves are described in the Amazon docs and are not part
of the code in this module.

More information about the API for various AWS services can be found
in the documentation at http://aws.amazon.com/documentation/

The code is under a BSD license, detailed in the LICENSE file.

LICENSE

Copyright (c) 2013, Evgeny Zislis

All rights reserved.

Redistribution and use in source and binary forms, with or without modification,
are permitted provided that the following conditions are met:

    * Redistributions of source code must retain the above copyright notice,
      this list of conditions and the following disclaimer.
    * Redistributions in binary form must reproduce the above copyright notice,
      this list of conditions and the following disclaimer in the documentation
      and/or other materials provided with the distribution.
    * Neither the name of `aws-api-engine` nor the names of its contributors
      may be used to endorse or promote products derived from this software
      without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

main.py

import urllib
from amazon.query import AmazonQuery

if __name__ == '__main__':
    key_id   = 'AKIAIEXAMPLEEXAMPLE6'
    secret   = 'example+example+example+example+example7'

    endpoint = 'https://cloudformation.us-west-1.amazonaws.com'
    question = { 'Version': '2010-05-15', 'Action': 'ListStacks' }

    endpoint = 'http://monitoring.us-west-1.amazonaws.com'
    question = { 'Version': '2010-08-01', 'Action': 'ListMetrics' }

    endpoint = 'http://ec2.us-west-1.amazonaws.com'
    question = { 'Version': '2012-03-01', 'Action': 'DescribeInstances' }
    question = { 'Version': '2012-03-01', 'Action': 'DescribeReservedInstancesOfferings' }
    question = { 'Version': '2012-03-01', 'Action': 'DescribeAvailabilityZones' }

    endpoint = 'http://elasticmapreduce.us-west-1.amazonaws.com'
    question = { 'Version': '2009-03-31', 'Action': 'DescribeJobFlows' }

    endpoint = 'http://ec2.us-east-1.amazonaws.com'
    question = { 'Version': '2012-10-01', 'Action': 'DescribeSpotPriceHistory' }

    endpoint = 'https://elasticache.us-west-1.amazonaws.com'
    question = { 'Version': '2011-07-15', 'Action': 'DescribeCacheClusters' }

    endpoint = 'https://rds.us-west-1.amazonaws.com'
    question = { 'Version': '2012-01-15', 'Action': 'DescribeDBEngineVersions' }

    endpoint = 'http://sns.us-west-1.amazonaws.com'
    question = { 'Version': '2010-03-31', 'Action': 'ListTopics' }

    endpoint = 'http://sqs.us-west-1.amazonaws.com'
    question = { 'Version': '2011-10-01', 'Action': 'ListQueues' }

    endpoint = 'http://sdb.us-west-1.amazonaws.com'
    question = { 'Version': '2009-04-15', 'Action': 'ListDomains' }

    endpoint = 'http://s3-us-west-1.amazonaws.com'
    question = { 'Version': '2006-03-01', 'Action': 'ListAllMyBuckets' }

    endpoint = 'https://elasticbeanstalk.us-east-1.amazonaws.com'
    question = { 'Version': '2010-12-01', 'Action': 'ListAvailableSolutionStacks' }

    endpoint = 'https://iam.amazonaws.com'
    question = { 'Version': '2010-05-08', 'Action': 'ListUsers' }

    endpoint = 'http://autoscaling.us-west-1.amazonaws.com'
    question = { 'Version': '2011-01-01', 'Action': 'DescribeTags' }

    endpoint = 'https://importexport.amazonaws.com'
    question = { 'Version': '2010-06-01', 'Action': 'ListJobs' }

    endpoint = 'https://sts.amazonaws.com'
    question = { 'Version': '2011-06-15', 'Action': 'GetSessionToken' }

    endpoint = 'https://iam.amazonaws.com'
    question = { 'Version': '2010-05-08', 'Action': 'GetUser' }
    question = { 'Version': '2010-05-08', 'Action': 'ListUserPolicies', 'UserName': 'test_iam' }
    question = { 'Version': '2010-05-08', 'Action': 'GetUserPolicy', 'UserName': 'test_iam', 'PolicyName': 'ReadOnlyAccess-test_iam-201203291722' }

    endpoint = 'http://elasticloadbalancing.us-west-1.amazonaws.com'
    question = { 'Version': '2011-11-15', 'Action': 'DescribeLoadBalancers' }

    query = AmazonQuery(endpoint, key_id, secret, question)
    print urllib.FancyURLopener().open(endpoint, query.signed_parameters).read()

query.py

import datetime
import urllib, urlparse
import hmac, hashlib, base64

class AmazonQuery(object):
    """
    Send a signed request to an Amazon AWS endpoint.

    :type endpoint: string
    :param endpoint: from http://docs.amazonwebservices.com/general/latest/gr/rande.html

    :type key_id: string
    :param key_id: The Access Key ID for the request sender.

    :type secret_key: string
    :param secret_key: Secret Access Key used for request signature.

    :type parameters: dict
    :param parameters: Optional additional request parameters.
    """

    def __init__(self, endpoint, key_id, secret_key, parameters=dict()):
        parsed = urlparse.urlparse(endpoint)
        self.host = parsed.hostname
        self.path = parsed.path or '/'
        self.endpoint = endpoint
        self.secret_key = secret_key
        self.parameters = dict({
            'AWSAccessKeyId': key_id,
            'SignatureVersion': 2,
            'SignatureMethod': 'HmacSHA256',
        }, **parameters)

    def signed_parameters(self):
        self.parameters['Timestamp'] = datetime.datetime.utcnow().isoformat()
        params = dict(self.parameters, **{ 'Signature': self.signature })
        return urllib.urlencode(params)
    signed_parameters = property(signed_parameters)

    def signature(self):
        params = urllib.urlencode( sorted(self.parameters.items()) )
        text = "\n".join(['POST', self.host, self.path, params])
        auth = hmac.new(self.secret_key, msg=text, digestmod=hashlib.sha256)
        return base64.b64encode(auth.digest())
    signature = property(signature)

test.py

import unittest

from amazon_query import AmazonQuery

class TestAmazonQuery(unittest.TestCase):
    def test_apicall_parameters(self):
        q = AmazonQuery('https://url.com', 'keyid', 'key',
                { 'Action': 'act', 'Version': '2012-03-01', 'foo': 'bar' })
        expected = {
            'Action': 'act',
            'Version': '2012-03-01',
            'AWSAccessKeyId': 'keyid',
            'SignatureVersion': 2,
            'SignatureMethod': 'HmacSHA256',
            'foo': 'bar',
        }
        self.assertDictContainsSubset(expected, q.parameters)
        self.assertDictContainsSubset(q.parameters, expected)

    def test_apicall_secret_key(self):
        q = AmazonQuery('https://url.com', 'keyid', 'key')
        self.assertEquals(q.secret_key, 'key')

if __name__ == '__main__':
    unittest.main()